1. Field of the Invention
The present invention relates generally to a system for automatically placing, filling and palletizing open mouth bags or valve bags and more specifically, to a bag packing center that is capable of automatically pre-conditioning a particulate material product, automatically placing bags onto a filler for filling the bags with the aforementioned product to a desired weight with substantial accuracy, automatically transferring the filled bag from the filler, flattening and shaping the bag to de-aerate the bag and automatically stacking the filled bags on a pallet in an interlocking pattern; the packing center providing an integrated and assembled unit which may be integrally transported to the user's place of business and operated in a manner to minimize manpower, floor space, utilities and other associated services for maximum operating efficiency.
2. Prior Art
The general concent of providing an automatic device for filling bags such as valve bags with particulate material is not new. By way of illustration the following U.S. patents disclosed prior art automatic bag filling apparatus which operates to permit a user to place empty valve bags into the system and retrieve filled valve bags from the system.
U.S. Pat. No. 4,334,558, issued June 15, 1982 to Durant PA1 U.S. Pat. No. 4,411,296, issued Oct. 25, 1983 to Durant
Furthermore, the concept of automatically palletizing valve bags is also not new. For example, U.S. Pat. No. 4,271,755 to Kintgen, et al discloses an automatic valve bag palletizing apparatus. Unfortunately, the valve bag filling and palletizing operations to this day remain distinctly separate and typically, the apparatus utilized for those separate operations are located in separate areas or rooms with conveyors spanning the distances between the apparatus. The user therefore is left with the problem of interface between the bag filler and the bag palletizer.
Typically, the bag filling apparatus manufacturer does not contemplate in his design that the user will have to palletize the filled bags generated by his system and merely leaves it to the user to appropriately transport the filled bags out of his system depending upon the user's specific requirements. Similarly, the manufacturer of the automatic palletizer does not typically contemplate the manner in which the user will bring the bags to the palletizer for appropriate transport and stacking. Thus, the user is left with the problem of integrating the two pieces of equipment and this integration problem is unique to the specific bag filling and palletizing systems that he has purchased. Furthermore, because neither of those systems is designed with the other in mind, often even if the user wishes to place the two systems in the same general proximity, it is difficult or impossible to do so because neither piece of equipment is designed with the space requirements of the other piece of equipment in mind. Thus, after a user has purchased an automatic valve bag placing and filling machine from one manufacturer and an automatic valve bag palletizer from another manufacturer and each such device has been shipped from the respective manufacturers to the user's place of business, the user must then incur the cost and time required to have an appropriate interface device designed, fabricated and assembled on his premises in order to facilitate the interaction between the respective pieces of equipment.
In addition to the above-mentioned difficulties, even after the appropriate interface mechanism has been designed, fabricated and assembled, the total system may not be the most efficient because as previously noted neither piece of equipment has been designed with the other in mind. Thus for example, the rate of placing and filling bags with particulate material may not be suitable for the rate at which such bags can be palletized by the other piece of equipment. Of course, there may also be occasions when the rate at which filled valve bags can be palletized by the automatic palletizer cannot accommodate the rate at which the bags are placed and filled by the other piece of equipment. In fact, the primary focus of automatic palletizer development during the last several years has been toward attaining greater rates of speed. Major advances have been made in developing units capable of handling for example, 25 to 40 bags per minute. To accommodate such a high rate palletizer, the user must have bags fed from conveyor lines which receive bags from several costly fillers ganged together to produce bags at the appropriate rates to match the palletizer.
Furthermore, a new picture has come into focus concerning the development of bag fillers. More specifically, with dramatic increases in the value of certain commodities filled into valve bags, particularly certain chemicals, the emphasis has changed for the filling operation from speed to accuracy. The development of electronic scales on the filler apparatus has made it possible to monitor weight at the filler. Electronic filling operations tend to further reduce filling rates due to the inherent electronic operation such as auto tare and checkweight feedback to control weight accuracies. Thus, it will be apparent that recent advances in the respective arts of palletizing and filling apparatus have in effect, further exacerbated the difficulties confronted by the user in regard to inherent incompatibilities between the bag placing and filling machinery on the one hand and the bag palletizing machinery on the other.
As a result, there has been a long-felt need in the marketplace for a fully automatic integrated packaging machine capable of filling bags to close weight tolerances and palletizing such bags at substantially the same rates at which they are filled. Furthermore, there has been a concurrent need for such a device which minimizes the cost of labor and which minimizes the facility space requirements to accommodate such a packing machine. There has also been a long-felt need for a packing machine which accepts empty open mouth bags or valve bags and produces fully and appropriately palletized filled bags and which is portable and thus can be transported to one or more of a user's locations as a unitary, integral unit requiring little or no special assembly at the user's location and which entirely obviates the aforementioned prior art requirement for unique transport mechanisms to integrate separate bag filling and bag palletizing machines.
With the recent demand for weight accuracy, the problems of proper product supply have also become vital to the successful filing operation. Unfortunately, this area also has been left to the user's discretion with only vague recommendation by the equipment supplier. The result is often non-existent or hapazard interlocks, feed controls and other devices between the infeed hopper and the filler and this often results in poor packer performance and difficulty in product changes, clean-out and the like irrespective of the capabilities of the filler and palletizer portions of the system. Thus, the aforementioned long-felt needs not adequately addressed by the prior art extend to the need to overcome the traditional barrier that has long existed between the packer product inlet and the user's supply bin outlet.